Improvement in projectiles for rifled ordnance



B. F. STURTEVANT.

Projectile.

Patented Aug. 5, 1862.

I Unirnn STATES Barnum Gimme;

A. BENJ. F. STUR-TEVANT, OF BOSTON, MASSACHUSETTS.

. lMPROVEMENT IN PROJECTILES FOR Rl-FLED ORDNANCE.

Specification forming part of Letters Patent No. 36,1196, dated August5, 1562.

f 0 all whom it may concern.-

- Be it known that I, BENJAMIN F. S'rUR'rE- VANT, a citizen of theUnited States of America, and a resident of Boston, in the county ofSuffolk and State of Massachusetts, have invented a new and usefulImprovement in Shells or Projectiles for Oannon'or Ordnance; andI dohereby declare the same to be fully described in the followingspecification and represented 1n the accompanying drawings, of whichFigure lis a side view, and Fig. 2 a longitudinal section, of a shell asprovided with my invention, the nature of which consists in theapplication of an annular enlargement or crossing groove and itsfilling-head with the annular neck and groove of the annular packing andbutt of a projectile; also, in a peculiar arrangement of two series ofinterlocking teeth with respect to the annular packing and itsholding-grooves.

The object of my invention is to so firmly secure the annular packing tothe body of the projectile as to prevent rupture of such packing and itsdetachment from the body of the projectile either at the period ofdischarge of the latter from a piece of ordnance or during its flighttherefrom.

It is well known that when a metallic packing of a projectile isruptured by the explosion of the charge by which the projectile may beexpelled from a gun, pieces of the packing are liable to be scattered invarious directions with great force, so as frequently to be produ ctiveof serious accidents to friendly troops, over whose heads it may benecessary to discharge the projectile at an enemy. My mode of connectingthe expansive packing to thebody of the projectile tends to effectuallyprevent such accidents.

In the drawings, A denotes the body of an elongated shell, while B isthe annular expansive metallic packing applied to its rear end. Thispacking I usually make of bronze or some composition of metals, such asby the force of explosion of the powder-charge of a gun may be expandedand driven closely against the bore ofthe piece, or into the grooves, incase such bore may be rifled or grooved. In affixing the packing B tothe body A, the latter is first cast or constructedwith an annulargroove, (1, extending within and around its rear portion and opening outof the same by means ofapassa-ge, b,narrowerthan the groove,

and arranged as shown in Fig. 3, which is a section of the rear part ofthe shell as it ap pears without the packing. its neck areso arrangedwithin the body A that there may be in advance of them an annularshoulder, c, for supporting the front edge of the metallic packing,which is subsequently to be cast about or around the rear part of theprojectile, and so as to enter and fill the neck b and the groove a, andextendin a hollow or tubular form a short distance rearward from therear end of the body, as shown in Fig. 2. The shoulder a, I form with aseries of cavities or teeth, as shown at d d (1, extending eitherpartially or entirely around it, and so that in the process of castingthe packing portions 6 'e e of it may run between these teeth and forminterlocking teeth, the whole being to prevent the packing from beingturned laterally in the annular groove a. That part of the packing whichextends into the groove a and its neck b, and is marked f in Fig. 2, maybe termed an annular tenon, having the form of a dovetail or anapproximation thereto, it being so arranged as to extend from the innersurface of the packing in such manner as not only to enable the packingto abut against the toothed or serrated shoulder a, but to have itsouter cylindric surface coincident with or in line with that of the bodyof the projectile, in manner as indicated by the drawings.

From the above it will be seen that my mode of connecting the expansivepacking to the butt of a shell or projectile will operate to greatadvantage, not only to prevent the pack ing from being ruptured anddriven forward on the projectile, both while it may be in a gun andunder the action of the force of an explosion of a charge thereof, butalso to secure the packing so strongly to the projectile as to preventsuch packing (in case of being ruptured) after it may have left thepiece, from flying in pieces and becoming detached from the projectileuntil the proper period for the shell to meet or strike the object atwhich it may be impelled.

I do not claim the invention either as claimed or represented in UnitedStates Patent numbered 15,999, for with such the annular cuppedcylinder, when broken, is easily detached from the butt of theprojectile, the entering tenon of it being made of an even thickness, orso as to slightly taper or decrease in thickness from This groove andits outer to its inner edge; but with my invention' the annulartenon andits groove have combined with them a second or transverse annulargroove, (1, and a head or filling thereof, they (the said transversegroove and head) fitting closely together and being made of greaterwidth than the annular neck or groove (4, and the Whole serving not onlyto give additional strength to the annular packing, but also to the rearpart of the shell. My improvement not only operates to prevent thepacking from being separated laterally from the body of the projectilewhile in flight through and beyond a gun, but enables the neck of thatpart ofthe projectile which is within the annular packing to be made sostrong as not to be liable to be broken off by the force of theexplosion of an expelling-charge while the prov -j ectile may bein theact of being driven through the bore of a gun. The arrangement of thetwo ranges of teeth of the packing and prothe packing, while beingexpanded, does not tend to separate the ranges of teeth, but rather toforce them into closer contact.

1. In combination with the annular neckgroove 1) and the part of theexpansive packing to enter the same, the annular enlargement or crossinggroove a and the metallic head or filling thereof.

2. The arrangement of the two series of interlocking teeth with respectto the annular packing and its holdinggrooves.

B. F. STURTEVANT.

Witnesses:

R. H. EDDY, F. P. HALE, J r.

